The U.S. Defense Department plans to put most of its 800,000 civilian employees on unpaid leave for 11 days to meet budget-cutting targets by the end of September.

Defense Secretary Chuck Hagel announced the plan Tuesday in a meeting with Pentagon employees.

The furlough is shorter than earlier estimates of up to 22 days. But Defense Department officials caution it could discourage civilians from joining the department, sending them instead to work in the private sector.

U.S. commanders have warned the reductions will undermine military readiness by forcing cuts to training and maintenance.

Under automatic budget cuts enacted by Congress, the Pentagon must slash its funding by roughly $37 billion this year.

Certain categories of employees may be exempt from the furloughs, including intelligence officers and shipyard workers.

The automatic budget reductions, or sequestration, were part of a 2011 law designed to contain the federal government's growing deficit and national debt.